import logging
from typing import Any, AsyncIterator, Dict, Iterator, List, Optional
from langchain_core._api.deprecation import deprecated
from langchain_core.callbacks import (
AsyncCallbackManagerForLLMRun,
CallbackManagerForLLMRun,
)
from langchain_core.language_models.llms import LLM
from langchain_core.outputs import GenerationChunk
from langchain_core.pydantic_v1 import Field, root_validator
from langchain_core.utils import get_pydantic_field_names, pre_init
logger = logging.getLogger(__name__)
[docs]@deprecated(
"0.0.21",
removal="1.0",
alternative_import="langchain_huggingface.HuggingFaceEndpoint",
)
class HuggingFaceTextGenInference(LLM):
"""
HuggingFace text generation API.
! This class is deprecated, you should use HuggingFaceEndpoint instead !
To use, you should have the `text-generation` python package installed and
a text-generation server running.
Example:
.. code-block:: python
# Basic Example (no streaming)
llm = HuggingFaceTextGenInference(
inference_server_url="http://localhost:8010/",
max_new_tokens=512,
top_k=10,
top_p=0.95,
typical_p=0.95,
temperature=0.01,
repetition_penalty=1.03,
)
print(llm.invoke("What is Deep Learning?")) # noqa: T201
# Streaming response example
from langchain_community.callbacks import streaming_stdout
callbacks = [streaming_stdout.StreamingStdOutCallbackHandler()]
llm = HuggingFaceTextGenInference(
inference_server_url="http://localhost:8010/",
max_new_tokens=512,
top_k=10,
top_p=0.95,
typical_p=0.95,
temperature=0.01,
repetition_penalty=1.03,
callbacks=callbacks,
streaming=True
)
print(llm.invoke("What is Deep Learning?")) # noqa: T201
"""
max_new_tokens: int = 512
"""Maximum number of generated tokens"""
top_k: Optional[int] = None
"""The number of highest probability vocabulary tokens to keep for
top-k-filtering."""
top_p: Optional[float] = 0.95
"""If set to < 1, only the smallest set of most probable tokens with probabilities
that add up to `top_p` or higher are kept for generation."""
typical_p: Optional[float] = 0.95
"""Typical Decoding mass. See [Typical Decoding for Natural Language
Generation](https://arxiv.org/abs/2202.00666) for more information."""
temperature: Optional[float] = 0.8
"""The value used to module the logits distribution."""
repetition_penalty: Optional[float] = None
"""The parameter for repetition penalty. 1.0 means no penalty.
See [this paper](https://arxiv.org/pdf/1909.05858.pdf) for more details."""
return_full_text: bool = False
"""Whether to prepend the prompt to the generated text"""
truncate: Optional[int] = None
"""Truncate inputs tokens to the given size"""
stop_sequences: List[str] = Field(default_factory=list)
"""Stop generating tokens if a member of `stop_sequences` is generated"""
seed: Optional[int] = None
"""Random sampling seed"""
inference_server_url: str = ""
"""text-generation-inference instance base url"""
timeout: int = 120
"""Timeout in seconds"""
streaming: bool = False
"""Whether to generate a stream of tokens asynchronously"""
do_sample: bool = False
"""Activate logits sampling"""
watermark: bool = False
"""Watermarking with [A Watermark for Large Language Models]
(https://arxiv.org/abs/2301.10226)"""
server_kwargs: Dict[str, Any] = Field(default_factory=dict)
"""Holds any text-generation-inference server parameters not explicitly specified"""
model_kwargs: Dict[str, Any] = Field(default_factory=dict)
"""Holds any model parameters valid for `call` not explicitly specified"""
client: Any
async_client: Any
class Config:
extra = "forbid"
@root_validator(pre=True)
def build_extra(cls, values: Dict[str, Any]) -> Dict[str, Any]:
"""Build extra kwargs from additional params that were passed in."""
all_required_field_names = get_pydantic_field_names(cls)
extra = values.get("model_kwargs", {})
for field_name in list(values):
if field_name in extra:
raise ValueError(f"Found {field_name} supplied twice.")
if field_name not in all_required_field_names:
logger.warning(
f"""WARNING! {field_name} is not default parameter.
{field_name} was transferred to model_kwargs.
Please confirm that {field_name} is what you intended."""
)
extra[field_name] = values.pop(field_name)
invalid_model_kwargs = all_required_field_names.intersection(extra.keys())
if invalid_model_kwargs:
raise ValueError(
f"Parameters {invalid_model_kwargs} should be specified explicitly. "
f"Instead they were passed in as part of `model_kwargs` parameter."
)
values["model_kwargs"] = extra
return values
@pre_init
def validate_environment(cls, values: Dict) -> Dict:
"""Validate that python package exists in environment."""
try:
import text_generation
values["client"] = text_generation.Client(
values["inference_server_url"],
timeout=values["timeout"],
**values["server_kwargs"],
)
values["async_client"] = text_generation.AsyncClient(
values["inference_server_url"],
timeout=values["timeout"],
**values["server_kwargs"],
)
except ImportError:
raise ImportError(
"Could not import text_generation python package. "
"Please install it with `pip install text_generation`."
)
return values
@property
def _llm_type(self) -> str:
"""Return type of llm."""
return "huggingface_textgen_inference"
@property
def _default_params(self) -> Dict[str, Any]:
"""Get the default parameters for calling text generation inference API."""
return {
"max_new_tokens": self.max_new_tokens,
"top_k": self.top_k,
"top_p": self.top_p,
"typical_p": self.typical_p,
"temperature": self.temperature,
"repetition_penalty": self.repetition_penalty,
"return_full_text": self.return_full_text,
"truncate": self.truncate,
"stop_sequences": self.stop_sequences,
"seed": self.seed,
"do_sample": self.do_sample,
"watermark": self.watermark,
**self.model_kwargs,
}
def _invocation_params(
self, runtime_stop: Optional[List[str]], **kwargs: Any
) -> Dict[str, Any]:
params = {**self._default_params, **kwargs}
params["stop_sequences"] = params["stop_sequences"] + (runtime_stop or [])
return params
def _call(
self,
prompt: str,
stop: Optional[List[str]] = None,
run_manager: Optional[CallbackManagerForLLMRun] = None,
**kwargs: Any,
) -> str:
if self.streaming:
completion = ""
for chunk in self._stream(prompt, stop, run_manager, **kwargs):
completion += chunk.text
return completion
invocation_params = self._invocation_params(stop, **kwargs)
res = self.client.generate(prompt, **invocation_params)
# remove stop sequences from the end of the generated text
for stop_seq in invocation_params["stop_sequences"]:
if stop_seq in res.generated_text:
res.generated_text = res.generated_text[
: res.generated_text.index(stop_seq)
]
return res.generated_text
async def _acall(
self,
prompt: str,
stop: Optional[List[str]] = None,
run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
**kwargs: Any,
) -> str:
if self.streaming:
completion = ""
async for chunk in self._astream(prompt, stop, run_manager, **kwargs):
completion += chunk.text
return completion
invocation_params = self._invocation_params(stop, **kwargs)
res = await self.async_client.generate(prompt, **invocation_params)
# remove stop sequences from the end of the generated text
for stop_seq in invocation_params["stop_sequences"]:
if stop_seq in res.generated_text:
res.generated_text = res.generated_text[
: res.generated_text.index(stop_seq)
]
return res.generated_text
def _stream(
self,
prompt: str,
stop: Optional[List[str]] = None,
run_manager: Optional[CallbackManagerForLLMRun] = None,
**kwargs: Any,
) -> Iterator[GenerationChunk]:
invocation_params = self._invocation_params(stop, **kwargs)
for res in self.client.generate_stream(prompt, **invocation_params):
# identify stop sequence in generated text, if any
stop_seq_found: Optional[str] = None
for stop_seq in invocation_params["stop_sequences"]:
if stop_seq in res.token.text:
stop_seq_found = stop_seq
# identify text to yield
text: Optional[str] = None
if res.token.special:
text = None
elif stop_seq_found:
text = res.token.text[: res.token.text.index(stop_seq_found)]
else:
text = res.token.text
# yield text, if any
if text:
chunk = GenerationChunk(text=text)
if run_manager:
run_manager.on_llm_new_token(chunk.text)
yield chunk
# break if stop sequence found
if stop_seq_found:
break
async def _astream(
self,
prompt: str,
stop: Optional[List[str]] = None,
run_manager: Optional[AsyncCallbackManagerForLLMRun] = None,
**kwargs: Any,
) -> AsyncIterator[GenerationChunk]:
invocation_params = self._invocation_params(stop, **kwargs)
async for res in self.async_client.generate_stream(prompt, **invocation_params):
# identify stop sequence in generated text, if any
stop_seq_found: Optional[str] = None
for stop_seq in invocation_params["stop_sequences"]:
if stop_seq in res.token.text:
stop_seq_found = stop_seq
# identify text to yield
text: Optional[str] = None
if res.token.special:
text = None
elif stop_seq_found:
text = res.token.text[: res.token.text.index(stop_seq_found)]
else:
text = res.token.text
# yield text, if any
if text:
chunk = GenerationChunk(text=text)
if run_manager:
await run_manager.on_llm_new_token(chunk.text)
yield chunk
# break if stop sequence found
if stop_seq_found:
break
